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    Chapter1

    1.AhospitalusesanapplicationthatstorespatientXraydataintheformoflargebinaryobjectsinanOracledatabase.TheapplicationishostedonaUNIXserver,andthehospitalstaffaccessestheXrayrecordsthroughaGigabitEthernetbackbone.AnEMCCLARiiONstoragearrayprovidesstoragetotheUNIXserver,whichhas6TBofusablecapacity.Explainthecoreelementsofthedatacenter.Whatarethetypicalchallengesthestoragemanagementteammayfaceinmeetingtheserviceleveldemandsofthehospitalstaff?Describehowthevalueofthispatientdatamightchangeovertime.

    Solution/Hint:

    Coreelementsofthedatacenter:ApplicationDatabaseoracle

    ServerandoperatingsystemUNIXserver

    NetworkLAN,SAN

    StoragearrayEMCCLARiiONstoragearrayChallenges:

    LongtermpreservationHighcost

    Howpatientdatamightchangeovertime:

    Forfirst60days,thepatientdataisaccessedfrequently

    Afterthattherequirementofthepatientdataisveryless,soitcouldbemovedtoCAS.

    2.Anengineeringdesigndepartmentofalargecompanymaintainsover600,000engineeringdrawingsthatitsdesigner'saccessandreuseintheircurrentprojects,modifyingorupdatingthemasrequired.Thedesignteamwantsinstantaccesstothedrawingsforitscurrentprojects,butiscurrentlyconstrainedbyan

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    infrastructurethatisnotabletoscaletomeettheresponsetimerequirements.Theteamhasclassifiedthedrawingsas"mostfrequentlyaccessed,""frequentlyaccessed,""occasionallyaccessed,"and"archive."

    SuggestandprovidethedetailsforastrategyforthedesigndepartmentthatoptimizesthestorageinfrastructurebyusingILM.

    Explainhowyouwilluse"tieredstorage"basedonaccessfrequency.

    Detailthehardwareandsoftwarecomponentsyouwillneedtoimplementyourstrategy.

    Researchproductsandsolutionscurrentlyavailabletomeetthesolutionyouareproposing.

    Solution/Hint:

    ClassifythedataaccordingtoaccessfrequencyorvalueandusetieredstoragethatoptimizestheinfrastructurecostandperformancebyusingILM.

    Storagerequirementcanbeclassifyas:

    frequentlyuseddatashouldbeplacedinhighendstoragearrayoccasionallyaccessedshouldbeinlowendstoragearrayandarchiveddatainspecializedCASsystem

    Hardwareandsoftwarecomponentsneeded:

    HighendandMidrangestoragearrayContentaddressedstorage(CAS)

    FCSAN,LANServer

    Software:

    ILMtool

    Researchonfollowingproductsandsolutions(www.emc.com)

    StoragearraysCLARiiON/Symmetrix

    CASCentera

    FCSANSwitches/DirectorsILMstrategy

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    3.Themarketingdepartmentatamidsizefirmisexpanding.Newhiresarebeingaddedtothedepartmentandtheyaregivennetworkaccesstothedepartment'sfiles.IThasgivenmarketinganetworkeddriveontheLAN,butitkeepsreachingcapacityeverythirdweek.Currentcapacityis500MB(andgrowing),withhundredsoffiles.UsersarecomplainingaboutLANresponsetimesandcapacity.AstheITmanager,whatcouldyourecommendtoimprovethesituation?Solution/Hint:

    NAS

    4.Alargecompanyisconsideringastorageinfrastructureonethatisscalableandprovideshighavailability.Moreimportantly,thecompanyalsoneedsperformanceforitsmissioncriticalapplications.Whichstoragetopologywouldyourecommend(SAN,NAS,IPSAN)andwhy?

    Solution/Hint:

    SANisarecommendedsolution.

    BecauseSANhashighscalabilityandavailability(usingdirectororswitch).

    Chapter2

    WhatarethebenefitsofusingmultipleHBAsonahost?Solution/Hint:

    Highavailability

    Anapplicationspecifiesarequirementof200GBtohostadatabaseandotherfiles.Italsospecifiesthatthestorageenvironmentshouldsupport5,000IOPSduringitspeakprocessingcycle.Thedisksavailableforconfigurationprovide66GBofusablecapacity,andthemanufacturerspecifiesthattheycansupportamaximumof140IOPS.Theapplicationisresponsetimesensitiveanddiskutilizationbeyond60percentwillnotmeettheresponsetimerequirementsoftheapplication.Computeandexplainthetheoreticalbasisfortheminimumnumberofdisksthatshouldbeconfiguredtomeettherequirementsoftheapplication.Solution/Hint:

    Numberofdiskrequired=max(sizerequirement,IOPSrequirements)Tomeetthesizerequirement=200GB/66GB=4disksTomeettheIOPSrequirement=5000IOPS/(140x0.6IOPS)=60disks=max(4,60)=60disks

    Whichcomponentsconstitutethediskservicetime?WhichcomponentcontributesthelargestpercentageofthediskservicetimeinarandomI/O

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    operation?Solution/Hint:

    seektime,rotationallatencyandtransferrate

    seektime

    Whydoformatteddiskshavelesscapacitythanunformatteddisks?Solution/Hint:

    Inordertomakestoragedevicefunctional,itneedtobeformatted.CommontypesofdriveformatsareFAT32,NTFSandext2.Ineachoftheformattingschemes,aportionofthestoragespaceisallocatedtoconfiguredfilesystemtoenablecatalogingdataonthediskdrive.

    TheaverageI/Osizeofanapplicationis64KB.Thefollowingspecificationsareavailablefromthediskmanufacturer:averageseektime=5ms,7,200rpm,transferrate=40MB/s.DeterminethemaximumIOPSthatcouldbeperformedwiththediskforthisapplication.Takingthiscaseasanexample,explaintherelationshipbetweendiskutilizationandIOPS.Solution/Hint:

    Thediskservicetime(Rs)isakeymeasureofdiskperformance;andRsalongwithdiskutilizationrate(U)determinestheI/Oresponsetimeforapplications.

    Thetotaldiskservicetime(Rs)isthesumofseektime(E),rotationallatency(L),andtheinternaltransfertime(X):Rs=E+L+X

    EisdeterminedbasedontherandomnessoftheI/Orequest.LandXaremeasuresprovidedbydiskvendorsastechnicalspecificationsofthedisk.Averageseektimeof5msinarandomI/Oenvironment,orE=5msDiskrotationspeedof7,200rpmfromwhichrotationallatency(L)canbedetermined,whichisonehalfofthetimetakenforafullrotationor

    L=(0.5/7,200rpmexpressedinms)40MB/sinternaldatatransferrate,fromwhichtheinternaltransfertime(X)isderivedbasedontheblocksizeoftheI/O.Withablocksizeof64KB,X=64KB/40MBConsequentlyRs=5ms+(0.5/7,200)+64KB/40MB=5+4.167+1.6=10.767ms

    Themaximumno.ofI/OsservicedpersecondorIOPS=1/RSInotherwords,foranI/Owithablocksizeof64KBand

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    Rs=10.767ms,themaximumIOPSwillbe1/(10.767*10"3)=92.876IOPS

    6.ConsideradiskI/OsysteminwhichanI/Orequestarrivesattherateof80IOPS.Thediskservicetimeis6ms.

    a.Computethefollowing:UtilizationofI/Ocontroller,Totalresponsetime,Averagequeuesize,andTotaltimespentbyarequestinaqueue.

    b.Computetheprecedingparameteriftheservicetimeishalved.Solution/Hint:

    Arrivalrate(a)=80IOPS,consequently,thearrivaltimeRa=1/a=1/80=12.5msRs=6ms(given)

    1.Utilization(U)=Rs/Ra

    =6/12.5=0.48or48%

    2.Responsetime(R)=Rs/(1U)

    =6/(10.48)=11.5ms

    3.Averagequeuesize=U/(1U)

    =(0.48)2/(l0.48)=0.44

    4.Timespentbyarequestinaqueue=UxR,orthetotalresponsetimeservicetime=0.48x11.5=5.52ms

    Now,ifcontrollerpowerisdoubled,ortheservicetimeishalved;consequentlyRs=3msinthisscenario.

    1.Utilization(U)=Rs/Ra=3/12.5=0.24or24%

    2.Responsetime(R)=Rs/(1U)=3/(10.24)=3.9ms

    3.Averagequeuesize=U2/(lU)=(0.24)2/(10.24)=0.08

    4.Timespentbyarequestinaqueue=0.24x3.9=0.936ms

    7.RefertoQuestion6andplotagraphshowingtheresponsetimeandutilization,considering20percent,40percent,60percent,80percent,and100percentutilizationoftheI/Ocontroller.Describetheconclusionthatcouldbederivedfromthegraph.Solution/Hint:

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    1.

    Utilization=20%=0.2

    Responsetime

    7.5ms

    2.

    Itili/ation=40

    %=0.4

    Responsetime=

    10ms

    3.

    Utilization=60

    %=0.6

    Responsetime

    15ms

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    4.

    1tiliAition=80

    %=0.8

    Responsetime

    30ms

    5.

    LUili/ation=100

    %=1

    Responsetime=

    infinity

    70i

    ^,,,,,,,,

    102030405060708090

    Utilization(%)

    Chapter3

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    1.WhyisRAID1notasubstituteforabackup?Solution/Hint:

    RAID1providesprotectionagainstdiskfailureandnotasolutionfordatarecoveryduetodisaster.

    2.WhyisRAIDnotanoptionfordataprotectionandhighavailability?Solution/Hint:

    Itdoesnotprovideanydataprotection.

    3.ExplaintheprocessofdatarecoveryincaseofadrivefailureinRAID5.Solution/Hint:

    ItperformsXORoperationbetweenremainingdisksandregeneratelostdata.

    4.WhatarethebenefitsofusingRAID3inabackupapplication?Solution/Hint:

    BackupapplicationperformslargesequentialI/OsandRAID3givesbestresultincaseoflargesequentialI/Ooperation.

    5.DiscusstheimpactofrandomandsequentialI/OindifferentRAIDconfigurations.

    Solution/Hint:

    RAID

    Random

    Sequential

    3

    Goodforrandomreadsandpoortofairforsmallrandomwrites.

    verygoodforsequentialreadsandgoodforlarge,sequentialwrites.

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    5

    Verygoodforrandomreads.Fairforrandomwrite.Slowerduetoparityoverhead.

    Goodforsequentialreads.Fairtogoodforsequentialwrites.

    1/0

    Verygoodforrandomwrite.

    Poortofairforsequentialwrites

    6.A10Krpmdriveisratedtoperform130IOPS,anda15Krpmdriveisratedtoperform180IOPSforanapplication.Theread/writeratiois3:1.ComputetheRAIDadjustedIOPSforthe10Kand15KdrivesforRAID1,RAID5,andRAID6.

    Solution/Hint:QuestionInvalid

    7.Anapplicationhas1,000heavyusersatapeakof2IOPSeachand2,000typicalusersatapeakof1IOPSeach,witharead/writeratioof2:1.Itisestimatedthattheapplicationalsoexperiencesanoverheadof20percentforotherworkloads.CalculatetheIOPSrequirementforRAID1,RAID3,RAID5,andRAID6.

    Solution/Hint:

    1000heavyusersatapeakof2IOPSeach=2000IOPS2000typicalusersatapeakof1IOPSeach=2000IOPS

    Assumemaximumconcurrency90%

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    [(2000+2000)*0.9]=3600hostbasedIOPSfor3000usersduringpeak

    activityperiod

    read/writeratio2:1

    8.ForQuestion7,computethenumberofdrivesrequiredtosupporttheapplicationindifferentRAIDenvironmentsif10Krpmdriveswitharatingof130IOPSperdrivewereused.

    Solution/Hint:

    NumberofdrivesrequiredtosupporttheapplicationindifferentRAIDenvironments,if10krpmdriveswitharatingof130IOPSperdrive

    ForRAID1ForRAID3ForRAID5ForRAID6

    3600*2/3+(2*1/3*3600)3600*2/3+(4*1/3*3600)3600*2/3+(4*1/3*3600)3600*2/3+(6*1/3*3600)

    4800IOPS7200IOPS7200IOPS9600IOPS

    ForRAID1=4800/130=37drivesForRAID3=7200/130=55drivesForRAID5=7200/130=55drivesForRAID6=9600/130=74drives

    Chapter4

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    1.ConsiderascenarioinwhichanI/Orequestfromtrack1isfollowedbyanI/Orequestfromtrack2onasectorthatis180degreesawayfromthefirstrequest.Athirdrequestisfromasectorontrack3,whichisadjacenttothesectoronwhichthefirstrequestismade.Discusstheadvantagesanddisadvantagesofusingthecommandqueuingalgorithminthisscenario.

    Solution/Hint:

    Inthisscenario,commandqueuingproviderotationallatencyoptimizationwhererequestfromtrack3isservicedbeforerequest2toavoidonerotationtiming.Assumeifrequest3isfromthesametrack1inthatcasecommandqueuingprovidesseektimeoptimizationandimprovesdiskperformance.

    2.WhichapplicationbenefitsthemostbybypassingthewritecacheandWhy?

    Solution/Hint:

    ApplicationwithverylargesizeI/Owrites.

    3.AnOracledatabaseusesablocksizeof4KforitsI/Ooperation.Theapplicationthatusesthisdatabaseprimarilyperformsasequentialreadoperation.Suggestandexplaintheappropriatevaluesforthefollowingcacheparameters:cachepagesize,cacheallocation(readversuswrite),prefetchtype,andwriteasidecache.

    Solution/Hint:

    Cachepagesize:4K

    Cacheallocation(readversuswrite):morereadcache

    prefetchtype:fixedprefetch

    Writeasidecache:Largevalue

    Chapter5

    1.DASprovidesaneconomicallyviablealternativetootherstoragenetworkingsolutions.Justifythisstatement.

    Solution/Hint:

    Setuprequiresarelativelylowerinitialinvestment

    Setupismanagedusinghostbasedtools,suchasthehostOS,whichmakes

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    storagemanagementtaskseasyforsmallandmediumenterprises.Requiresfewermanagementtasks,andlesshardwareandsoftwareelementstosetupandoperate.

    2.HowistheprioritysequenceestablishedinawideSCSIenvironment?Solution/Hint:

    InawideSCSI,thedeviceIDsfrom8to15havethehighestpriority,buttheentiresequenceofwideSCSIIDshaslowerprioritythannarrowSCSIIDs.Therefore,theoverallprioritysequenceforawideSCSIis7,6,5,4,3,2,1,0,15,14,13,12,11,10,9,and8.

    3.WhyisSCSIperformancesuperiortothatofIDE/ATA?Explainthereasonsfromanarchitecturalperspective.

    Solution/Hint:

    SCSIoffersimprovedperformanceandexpandabilityandcompatibilityoptions,makingitsuitableforhighendcomputers.Numberofdevicessupportedis16

    SCSIarchitecturederivesitsbasefromtheclientserverrelationshipSCSIinitiator,oraclient,sendsarequesttoaSCSItarget,oraserver.ThetargetperformsthetasksrequestedandsendstheoutputtotheinitiatorWhenadeviceisinitialized,SCSIallowsforautomaticassignmentofdeviceIDsonthebus,whichpreventstwoormoredevicesusingthesameSCSIIDs.

    4.ResearchbladeserverarchitectureanddiscussthelimitationsofDASforthisarchitecture.

    Solution/Hint:DASLimitations

    DASdoesnotscalewell,hasalimitednumberofports

    AlimitedbandwidthinDASrestrictstheavailableI/Oprocessingcapability.

    ThedistancelimitationsassociatedwithDAS

    Inabilitytosharetheresources,unusedresourcescannotbeeasilyreallocated,resultinginislandsofoverutilizedandunderutilizedstoragepools.

    5.WhatwouldyouconsiderwhilechoosingserialorparalleldatatransferinaDASimplementation?Explainyouranswerandjustifyyourchoice.

    Solution/Hint:

    DistanceandspeedarethekeyfactorsSerialdatatransfercanovercomethedistancelimitationsParalleldatatransfercanovercometheseedlimitationsParalleldatatransferissuitableforInternalDAS

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    SerialdatatransferissuitableforExternalDAS

    6.Ifthreeharddiskdrivesareconnectedinadaisychainandcommunicateover

    SCSI,explainhowtheCPUwillperformI/Ooperationswithaparticulardevice.Solution/Hint:

    Eachdiskwillbeidentifiedbycn|tn|dnnumber

    Asthethreedisksareconnectedinadaisychaincnandtnnumberwillbethesameforallthedisks

    SCSIcommands/responsewillbeusedforthecommunication

    Chapter6

    1.Whatiszoning?Discussascenario,

    (i)wheresoftzoningispreferredoverhardzoning.

    (ii)wherehardzoningispreferredoversoftzoning.Solution/Hint:

    ZoningisanFCswitchfunctionthatenablesnodeswithinthefabrictobelogicallysegmentedintogroupsthatcancommunicatewitheachother.Azoneconsistsofselecteddevices,suchashostbusadapters(HBAs)andstoragedevices,inthefabric.Devicesassignedtoonezonecancommunicatewithotherdevicesinthesamezone,butnotwithdevicesinzonesofwhichtheyarenotmembers.Thiszoningpracticeprovidesafast,efficient,andreliablemeansofcontrollingtheHBAdiscovery/loginprocess.Withoutzoning,theHBAwillattempttologintoallportsonthefabricduringdiscoveryandduringtheHBA'sresponsetoastatechangenotification.Withzoning,thetimeandFibreChannelbandwidthrequiredtoprocessdiscoveryandthestatechangenotificationareminimized.

    (i)SoftzoningisalsocalledWWNzoninganditispreferredwhenuserneedflexibilitytophysicallymoveattachednodesbetweenswitchportsrecabletheSAN,thatmaytakeplaceduringswitchmaintenanceandrepairwithoutreconfiguringthezoneinformation.ThisispossiblebecausetheWWNisstatictothenodeport.

    (ii)Hardzoningisalsocalledportzoning,itisconvenientwhenthereisaneedforhardwarereplacementasWWNisuniquelyassociatedwithahardware.

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    2.DescribetheprocessofassigningFCaddresstoanodewhenloggingintothenetworkforthefirsttime.

    Solution/Hint::

    Tologontothefabric,anodesendsaFLOGIframewiththeWorldWideNodeName(WWNN)andWorldWidePortName(WWPN)parameterstotheloginserviceatthewellknownFCaddressFFFFFE.Inturn,theswitchacceptstheloginandreturnsanAccept(ACC)framewiththeassignedFCaddressforthedevice.ImmediatelyaftertheFLOGI,theN_portregistersitselfwiththelocalnameserverontheswitch,indicatingitsWWNN,WWPN,andassignedFCaddress.

    3.Seventeenswitches,with16portseach,areconnectedinameshtopology.Howmanyportsareavailableforhostandstorageconnectivityifyoucreateahighavailabilitysolution?

    Solution/Hint:

    Totalports=17*16=272

    NumberofISL136

    EachISLconsumes2ports

    numberofportsavailableforhosts

    4.DiscusstheadvantageofFCSWoverFCAL.

    Solution/Hint::

    Unlikealoopconfiguration,aFibreChannelswitchedfabric(FCSW)networkprovidesinterconnecteddevices,dedicatedbandwidth,andscalability.Theadditionorremovalofadeviceinaswitchedfabricisminimallydisruptive;itdoesnotaffecttheongoingtrafficbetweenotherdevices(ascomparedtoFCAL).InFCSW,nodesdonotsharealoop;instead,dataistransferredthroughadedicatedpathbetweenthenodes.FCuses24bitfibrechanneladdressingschemeforconnectivitywhichcansupportupto15milliondevices(FCALuses8bitaddressingwhichcansupportupto127devicesonaloop)

    5.HowflowcontrolworksinFCnetwork.Solution/Hint::

    Flowcontrolisusedtodefineandregulatethepaceofflowofdataframesbetweensenderandreceiverduringdatatransmission.FCtechnologyusestwoflowcontrolmechanisms:buffertobuffercredit(BBCredit)andendtoendcredit(EECredit).

    BB_Credit:Theprocessisasfollows

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    1.Atlogin,thetransmitterandthereceiverexchangeparametersandestablishtheBBCreditvalue.

    2.Thetransmitter'scountinitializestotheBBCreditvalue.

    3.If(BBCredit>0),transmittersendsaframe,anddecrementsthecountpertransmittedframe.

    4.AnRRDY(ReceiverReady)issentfromthereceivingporttothetransmittingportforeveryavailablebufferonthereceivingside.

    5.Thetransmitterincrementsthecountby1foreachRRDYitreceivesfromthereceiver.Thetransmittingportmaintainsacountoffreereceiverbuffers.

    5.Uponalinkreset,theBBCreditvalueresetstothevaluenegotiateduponlogin.

    EE_Credit

    Thefunctionofendtoendcredit,knownasEECredit,issimilartothatofBB_Credit.(TheEECreditmechanismisusedfortheflowcontrolforclass1andclass2trafficonly).

    6.Whyisclass3servicemostpreferredforFCcommunication?Solution/Hint:

    NondedicatedconnectionBBcredit

    HighbandwidthutilizationSupportformultiplexing

    Chapter7

    1.ListandexplaintheconsiderationsforcapacitydesignforbothCPUandstorageinaNASenvironment.

    Solution/Hint:

    ThescalabilityofcapacitycanbeaconstraintinanintegratedNAS.However,thegatewayNAScanscalefortherequiredconnectivityandstorage.GatewayNASsharesCPUloadwithSANworkloadandmayfaceconstraintonCPUutilization.Typically,CPUcapacityisnotthemajorbottleneckfactorinaNASsystem,butotherconsiderationssuchasmemoryrequirement,numberofnetworkports,filesystem,IOPSrequirements,alongwithstoragecapacityrequirementsareimportantfactor.

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    2.SANisconfiguredforbackuptoadiskenvironment,andthestorageconfigurationhasadditionalcapacityavailable.CanyouhaveaNASgatewayconfigurationusethisSAN?DiscusstheimplicationsofsharingthebackuptodiskSANenvironmentwithNAS.

    Solution/Hint:

    AstheadditionalcapacityisavailablegatewayNAScanbeimplemented.ButduringthebackupwindowitwillhaveconsiderableperformanceimpactonNetworkandhenceNAS.

    3.ExplainhowtheperformanceofNAScanbeaffectediftheTCPwindowsizeatthesenderandthereceiverarenotsynchronized.

    Solution/Hint:

    ThiswillaffecttheNASperformanceasthismayleadtoretransmissionofdata,lowerbandwidthutilization,performancedegradationofthenetwork,intermittentconnectivity,anddatalinkerrors.

    4.ResearchtheuseofbabyjumboframesandhowitaffectsNASperformance.Solution/Hint:

    CommonEthernetJumboframesizeis9000BytesBabyjumboframessizeis2.5KBBytes

    5.ResearchthefilesharingfeaturesoftheNFSprotocol.

    Hint:Researchquestion(refertoNFSprotocolsectioninthebook)

    6.ANASimplementationconfiguredjumboframesontheNAShead,with9,000asitsMTU.However,theimplementersdidnotseeanyperformanceimprovementandactuallyexperiencedperformancedegradation.Whatcouldbethecause?Researchtheendtoendjumboframesupportrequirementsinanetwork.

    Solution/Hint:

    Jumboframesareusedattheendpoint(NASHead)withMTUof9000CheckiftheintermediatenetworkusesadifferentMTUsize(e.g.1500).ThiscancausetheroutertodroppacketswhichthenhavetoretransmitattheTCPlayer.

    PacketsarethenfragmentedandhavetoreassembletoaccommodatethedifferentMTUsizes.Thisdegradesnetworkperformance.

    7.AcmeCorporationistryingtodecidebetweenanintegratedoragatewayNASsolution.TheexistingSANatAcmewillprovidecapacityandscalability.TheIT

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    departmentisconsideringaNASsolutionfortheTrainingdepartmentatAcmefortrainingvideos.Thevideoswouldonlybeusedbythetrainingdepartmentforevaluationofinstructors.PickaNASsolutionandexplainthereasonsforyourchoice.Solution/Hint:

    ExistingSAN;sothechoicewillbegatewayNASCheckifSANhasadditionalcapacityavailable.

    Chapter8

    1.HowdoesiSCSIhandletheprocessofauthentication?Researchtheavailableoptions.

    Solution/Hint::

    CHAP(Challengehandshakeauthenticationprotocol)

    2.ListsomeofthedatastorageapplicationsthatcouldbenefitfromanIPSANsolution.

    Solution/Hint:

    ExtendingreachofexistingSANDisasterrecoverysolutionsRemoteofficeapplications

    3.WhatarethemajorperformanceconsiderationsforFCIP?Solution/Hint:

    Refersection8.2.2FCIPPerformanceandsecurity

    4.ResearchthemultipathingsoftwareavailableforaniSCSIenvironment.WriteatechnicalnoteonthefeaturesandfunctionalityofEMCPowerPathsupportforiSCSI.

    Hint:Researchwork

    5.ResearchtheiSCSIcapabilitiesinaNASdevice;provideusecaseexamples.Hint:Researchwork

    6.Acompanyisconsideringimplementingstorage.Theydonothaveacurrentstorageinfrastructuretouse,buttheyhaveanetworkthatgivesthemgoodperformance.DiscusswhethernativeorbridgediSCSIshouldbeusedandexplainyourrecommendation.

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    Solution/Hint:

    NativeiSCSIimplementationdoesn'tinvolveanyFCcomponentswhile

    BridgediSCSIimplementationinvolvesFCcomponents

    Asthecompanydoesn'thavestorageinfrastructureandthenetworktheyhave

    givesthemagoodperformancenativeiSCSIshouldbedeployed.

    iSCSIenabledStorageisonlyneededifnativeiSCSIistobeimplementedin

    thiscase.

    7.TheIPbandwidthprovidedforFCIPconnectivityseemstobeconstrained.DiscussitsimplicationsiftheSANsthataremergedarefairlylarge,with500portsoneachside,andtheSANsatbothendsareconstantlyreconfigured.

    Solution/Hint:

    AsbandwidthisinsufficientIPnetworkwillbecomethebottleneckAsthefabricsonbothsidesarefairlylargeandareconstantlyreconfiguredanydisruptionintheIPnetworkwillleadtoinstabilitiesinunifiedfabric.Theseincludeasegmentedfabric,excessiveRSCNs,andhosttimeouts.

    ThesolutioncanbetosegregateFCIPtrafficintoaseparatevirtualfabric,toprovideadditionalstability,

    8.ComparedtoastandardIPframe,whatpercentageofreductioncanberealizedinprotocoloverheadinaniSCSIconfiguredtousejumboframeswithanMTUvalueof9,000?

    Solution/Hint:

    iSCSIPDUsize=1460bytes(containpayloadandadditionalheadersegment)Jumboframesizeof9000MTUoutofwhichpayloadis8960JumboFramesallowsasignificantamountofincreasedpayloadtobedeliveredineachiSCSIPDU.

    9.WhyshouldanMTUvalueofatleast2,500beconfiguredinabridgediSCSIenvironment?

    Solution/Hint:

    FCsupportsframesizeof2148byte

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    Chapter9

    1.ExplainhowaCASsolutionfitsintotheILMstrategy.Solution/Hint:

    AccordingtoILMstrategyvalueofinformationchangesoveritslifecycle,whencreatedvalueofinformationisveryhighanditisfrequentlyaccessedandchanged,henceplacedinahighperformancecostlystorage.Withthetimeitsvaluedropsanditbecomesfixedcontentwhichisrarelyaccessed,butstillholdsplaceincostlystoragespace.Forthecostoptimizationlessaccesseddatashouldbemovedtoarchivedandleavethecostlyspaceforhighvaluedata.CASisasolutionforarchiveddata,whichnotonlyprovidecostbenefitbutalsoprovidefasteraccessandreliablestoragetofixedcontent.

    2.ToaccessdatainaSAN,ahostusesaphysicaladdressknownasalogicalblockaddress(LBA).AhostusingaCASdevicedoesnotuse(orneed)aphysicaladdress.Why?

    Solution/Hint:

    Unlikefilelevelandblockleveldataaccessthatusefilenamesandthephysicallocationofdataforstorageandretrieval,CASstoresdataanditsattributesasanobject.Thestoredobjectisassignedagloballyuniqueaddressknownasacontentaddresswhichisderivedfromtheactualbinaryrepresentationofstoreddata.

    3.TheITdepartmentofadepartmentalstoreusestapetoarchivedata.Explain45majorpointsyoucouldprovidetopersuadetheITdepartmenttomovetoaCASsolution.HowwouldyoursuggestionsimpacttheITdepartment?

    Solution/Hint:

    GuaranteedContentAuthenticityandIntegrity:Datacannotbemanipulated

    oncestored,meetregulatoryandbusinesscompliance.

    SingleInstanceStorage:Simplifiesstorageresourcemanagement,especially

    whenhandlinglargeamountoffixedcontent.

    FasterDataRetrieval:Comparedtotape

    Technologyindependence:Aslongastheapplicationserverisabletomaptheoriginalcontentaddressthedataremainsaccessible.

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    Betterdataprotectionanddisposition:AllfixedcontentisstoredinCASonceandisbackedupwithaprotectionscheme.

    Chapter10

    1.WhatdoVLANsvirtualize?DiscussVLANimplementationasavirtualizationtechnology.

    Solution/Hint:

    VLANstandforvirtualLANwhichhassameattributesasofphysicalLAN,butallowshoststobegroupedtogethereveniftheyarenotlocatedonthesamenetworkswitch.Withtheuseofnetworkreconfigurationsoftware,portsonthelayer2switchcanbelogicallygroupedtogether,formingaseparate,VirtualLocalAreaNetwork.VLANshelptosimplifynetworkadministration.PortsinaVLANcanbelimitedtoonlythenumberneededforaparticularnetwork.ThisallowsunusedportstobeusedinotherVLANs.Throughsoftwarecommands,additionalportscanbeaddedtoanexistingVLANiffurtherexpansionisneeded.IfamachineneedstobemovedtoadifferentIPnetwork,theportisreassignedtoadifferentVLANandthereisnoneedforthephysicalmovementofcables.

    3.Howcanablocklevelvirtualizationimplementationbeusedasadatamigrationtool?Explainhowdatamigrationwillbeaccomplishedanddiscusstheadvantagesofusingthismethodforstorage.Comparethismethodtotraditionalmigrationmethods.

    Solution/Hint:

    Conventionallydatamigrationneedsphysicalremappingofserverstonewstoragelocationwhichresultedinapplicationdowntimeandphysicalchanges.Inavirtualizedenvironmentvirtualvolumesareassignedtothehostoutofphysicalpoolofstoragecapacity.Datamigrationisachievedthroughthesevirtualvolumes.Tomoveavirtualvolume,virtualizationsoftwareperformsaredirectionofLOfromonephysicallocationtoanother.DespitethefactthattheLOisphysicallyredirectedtoanewlocationbythevirtualizationsoftware,theaddressofthevirtualvolumepresentedtothehostneverchanges.Thisisaccomplishedthroughvirtualaddressing.Thisallowstheprocesstobetransparentandnondisruptivetothehost.Additionally,sincethecopyingandremappingisdonebythevirtualizationsystem,nohostcyclearerequired,freeingserverstobededicatedtotheirproperapplicationcentricfunction.

    Chapter11

    1.Anetworkrouterhasafailurerateof0.02percentper1,000hours.Whatisthe

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    MTBFofthatcomponent?

    Solution/Hint:

    MTBFofnetworkrouter=1/Failurerate

    =100*1000/0.02=50,00,000hrs

    2.TheITdepartmentofabankpromisescustomeraccesstothebankratetablebetween9:00a.m.and4:00p.m.fromMondaytoFriday.Itupdatesthetableeverydayat8:00a.m.withafeedfromthemainframesystem.Theupdateprocesstakes35minutestocomplete.OnThursday,duetoadatabasecorruption,theratetablecouldnotbeupdated,andat9:05a.m.,itwasestablishedthatthetablehaderrors.Arerunoftheupdatewasdone,andthetablewasrecreatedat9:45a.m.Verificationwasrunfor15minutes,andtheratetablebecameavailabletothebankbranches.Whatwastheavailabilityoftheratetablefortheweekinwhichthisincidenttookplace,assumingtherewerenootherissues?

    Solution/Hint:

    Availability=totaluptime/totalscheduledtimeTotalscheduledtime=7hrs*5=35hrs

    Totaluptime=34hrs(asonThursdayratetablewasmadeavailableat10:00aminsteadof9:00am)

    Therefore,availabilityoftheratetablefortheweek=34/35

    3.'Availabilityisexpressedintermsof9s."Explaintherelevanceoftheuseof9sforavailability,usingexamples.

    Solution/Hint:

    Uptimeperyearisbasedontheexacttimelinessrequirementsofthe

    service,thiscalculationleadstothenumberof"9s"representationforavailabilitymetrics.

    Forexample,aservicethatissaidtobe"five9savailable"isavailablefor99.999percentofthescheduledtimeinayear(24x7x365).

    Uptime(%)Downtime(%)DowntimeperDowntimeper

    YearWeek

    99.9990.0015.25minutes6sec

    4.Provideexamplesofplannedandunplanneddowntimeinthecontextofdatacenteroperations.

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    Solution/Hint:

    Examplesofplanneddowntime:installation/integration/maintenanceofnewhardware,softwareupgradesorpatches,takingbackups,application

    anddatarestores,facilityoperations(renovationandconstruction),refresh/migrationoftestingenvironmenttotheproductiondata

    Examplesofunplanneddowntime:failurecausedbydatabasecorruption,componentfailure,humanerrors

    5.HowdoesclusteringhelptominimizeRTO?Solution/Hint:

    RTOof1hour:Clusterproductionserverswithcontrollerbaseddiskmirroring.

    RTOofafewseconds:Clusterproductionserverswithbidirectionalmirroring,enablingtheapplicationstorunatbothsitessimultaneously.

    6.Howisthechoiceofarecoverysitestrategy(coldandhot)determinedinrelationtoRTOandRPO?

    Solution/Hint:

    RTOandRPOsmallhotsite

    RTOandRPOlargecoldsite

    7.Assumethestorageconfigurationdesignshowninthefollowingfigure:

    Performthesinglepointoffailureanalysisforthisconfigurationandprovideanalternateconfigurationthateliminatesallsinglepointsoffailure.

    Solution/Hint:

    Singlepointoffailure:host,switch,storagearray,HBA,arrayportandpath

    AlternateconfigurationasshownbelowtoavoidSPF

    Host

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    StorageArray

    t.iuslhimiISkrhrh

    RedundantFCSwitcherI

    Chapter12

    1.Amanufacturingcorporationusestapeasitsprimarybackupstoragemediathroughouttheorganization:

    FullbackupsareperformedeverySunday.

    IncrementalbackupsareperformedMondaythroughSaturday.

    Theenvironmentcontainsmanybackupservers,backingupdifferentgroupsofservers.

    Theemailanddatabaseapplicationshavetobeshutdownduringthebackupprocess.

    Duetothedecentralizedbackupenvironment,recoverabilityisoftencompromised.Therearetoomanytapesthatneedtobemountedtoperformafullrecoverincaseofacompletefailure.Thetimeneededtorecoveristoolengthy.Thecompanywouldliketodeployaneasytomanagebackupenvironment.Theywanttoreducetheamountoftimetheemailanddatabaseapplicationsareunavailable,andreducethenumberoftapesrequiredtofullyrecoveraserverincaseoffailure.

    Proposeabackupandrecoverysolutiontoaddressthecompany'sneeds.Justifyhowyoursolutionensuresthattheirrequirementswillbemet.

    Solution/Hint:

    Thesolutionshouldhavethefollowingelements:

    Centralizedbackupserver

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    Backupagentstoavoidtherequirementforcriticalapplicationstobeshutdownduringthebackupprocess.

    Useofacumulativebackuppolicyinsteadofincrementalbackups,reducingtheamountoftaperequiredforafullrestore.

    2.TherearelimitedbackupdevicesinafilesharingNASenvironment.Suggestasuitablebackupimplementationthatwillminimizethenetworktraffic,avoidanycongestion,andatthesametimenotimpacttheproductionoperations.Justifyyouranswer.

    Solution/Hint:

    ThisisachievedbytheintroductionofNDMP,topromotedatatransportbetweenNASandbackupdevices.Duetoitsflexibilityitisnolongernecessarytotransportthedatathroughthebackupserver.Dataissentfromthefilerdirectlytothebackupdevice,whilemetadataissenttothebackupserverfortrackingpurposes.Thissolutionmeetsthestrategicneedtocentrallymanageandcontroldistributeddata,whileminimizingnetworktraffic.NDMP3wayisusefulwhentherearelimitedbackupdevicesintheenvironment,enablingtheNASdevicecontrollingthebackupdevicetoshareitwithotherNASdevices,byreceivingbackupdataviaNDMP.

    3.Discussthesecurityconcernsinbackupenvironment.

    Solution/Hint:

    Majorsecurityconcerninbackupenvironmentisspoofingbackupserver,backupclientorbackupnodeidentitybyunauthorizedhost,togainaccesstobackupdata.Anotherconcernisbackuptapebeinglost,stolen,ormisplaced,especiallyifthetapescontainhighlyconfidentialinformation.Backuptotapeapplicationsarealsovulnerabletosecurityimplicationsiftheydonotencryptdatawhilebackingup.Lastlybackupdatashreddingshouldalsoconsider,byperformingsafetapedataerasureoroverwritingiftheynolongerrequired.

    4.Whatarethevariousbusiness/technicalconsiderationsforimplementingabackupsolution,andhowdotheseconsiderationsimpactthebackupsolution/

    implementation?

    Solution/Hint:

    >RTOandRPOaretheprimaryconsiderationsinselectingandimplementinga

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    >specificbackupstrategy.

    >Retentionperiod

    >Backupmediatype

    >Backupgranularity

    >Timeforperformingbackupandavailablebackupwindow

    >Locationandtimeoftherestoreoperation

    >filecharacteristics(location,size,andnumberoffiles)anddatacompression

    5.Whatisthepurposeofperformingoperationbackup,disasterrecovery,andarchiving?

    Solution/Hint:

    Operationbackup:TorestoredataintheeventofdatalossorlogicalcorruptionsDisasterrecovery:Forrestoringdataatanalternatesitewhentheprimarysiteis

    incapacitatedduetoadisaster.Archiving:Forlongtermdataretention(regulatorycomplianceorbusiness

    requirement)

    6.Listandexplaintheconsiderationsinusingtapeasthebackuptechnology.Whatarethechallengesinthisenvironment?

    Solution/Hint:

    Advantages:

    Offsitedatacopy

    LowerinitialcostChallenges:

    Reliability

    Restoreperformance(mount,loadtoready,rewind,dismounttimes)

    SequentialAccess

    HVACcontrolledenvironment

    Shipping/handlingchallenges

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    7.Describethebenefitsofusing"virtualtapelibrary"over"physicaltapes."

    Features

    Tape

    VirtualTape

    OffsiteCapabilities

    Yes

    Yes

    Reliability

    Noinherentprotectionmethods

    RAID,spare

    Performance

    Subjecttomechanicaloperations,loadtimes

    Fastersinglestream

    Use

    Backuponly

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    Backuponly

    Chapter13

    1.Whatistheimportanceofrecoverabilityandconsistencyinlocalreplication?Solution/Hint:

    Recoverabilityenablesrestorationofdatafromthereplicastotheproductionvolumesintheeventofdatalossordatacorruption.RecoverabilitymustprovideminimalRPOandRTOforresumingbusinessoperationsontheproductionvolumes.

    Consistencyensurestherestartabilityfromdata.Businessoperationcannotresumefrominconsistentdata.

    2.Describetheusesofalocalreplicainvariousbusinessoperations.

    Solution/Hint:

    AlternatesourceforbackupFastrecovery

    DecisionsupportactivitiessuchasreportingTestingplatformDatamigration

    3.Whataretheconsiderationsforperformingbackupfromalocalreplica?

    Solution/Hint:

    ThereplicashouldbeconsistentPITcopyofthesourceReplicashouldnotbeupdatedwhenthebackupwindowisopen

    4.Whatisthedifferencebetweenarestoreoperationandaresynchronizationoperationwithlocalreplicas?Explainwithexamples.

    Solution/Hint:

    Restoreoperation

    Sourceissynchronizedwiththetargetdata

    Forexample,ifsourcecontainsadatabasewherealogicaldatacorruptionoccurs,thedatacanberecoveredbyattachingthelatestPITreplicaofthesourceandmakingincrementalrestoreoperation.Resynchronizationoperation

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    Targetissynchronizedwiththesourcedata

    Forexample,aftertargetisdetachedfromthesource,bothsourceandtargetdataareupdatedbythehost.Aftersometimethetargetneedstobesynchronizedwiththesourcedata.Forthat,targetisagainattachedtothesourceandincrementalresynchronizationisperformed.

    5.A300GBdatabaseneedstwolocalreplicasforreportingandbackup.Thereareconstraintsinprovisioningfullcapacityforthereplicas.Ithasbeendeterminedthatthedatabasehasbeenconfiguredon15disks,andthedailyrateofchangeinthedatabaseisapproximately25percent.Youneedtoconfiguretwopointer

    basedreplicasforthedatabase.Describehowmuchcapacityyouwouldallocateforthesereplicasandhowmanysavevolumesyouwouldconfigure.

    Solution/Hint:

    75GBofsavevolumesarerequired

    space/capacityisallocated,sinceitispointerbasedreplica

    6.ForthesamedatabasedescribedinQuestion5,discusstheadvantagesofconfiguringfullvolumemirroringiftherearenoconstraintsoncapacity.

    Solution/Hint:

    Infullvolumemirroring,thesourceneednotbeup/healthyforrecovery.

    7.AnadministratorconfiguressixsnapshotsofaLUNandcreateseightclonesofthesameLUN.Theadministratorthencreatesfoursnapshotsforeachclonethatwascreated.Howmanyusablereplicasarenowavailable?

    Solution/Hint:

    Usablereplicas=6+8+32=46

    8.RefertoQuestion5.Havingcreatedthetworeplicasforbackupandreportingpurposes,assumeyouarerequiredtoautomatetheprocessesofbackupandreportingfromthereplicasbyusingascript.Developascriptinapseudolanguage(youcanusethestandardTimeFindercommandsfortheoperationsyouneedtoperform)thatwillfullyautomatebackupandreporting.Yourscriptshouldperformalltypesofvalidationsateachstep(e.g.,validatingwhetherasynchronizationprocessiscompleteoravolumemountissuccessfullydone).

    Solution/Hint:

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    Createaflowchartinsimplelanguage.

    Chapter14

    1.Anorganizationisplanningadatacentermigration.Theycanonlyaffordamaximumoftwohoursdowntimetocompletethemigration.Explainhowremotereplicationtechnologycanbeusedtomeetthedowntimerequirements.Whywilltheothermethodsnotmeetthisrequirement?

    Solution/Hint:

    SANbasedremotereplicationtechnologycanbeusedtoavoidthedowntimeasitprovidenondisruptivedatamigration.Conventionalmethodsneeddowntimetomigratedatafromonelocationtoother.

    2.ExplaintheRPOthatcanbeachievedwithsynchronous,asynchronous,anddiskbufferedremotereplication.

    Solution/Hint:

    RPOthatcanbeachievedwithsynchronousoftheorderofSecondsRPOthatcanbeachievedwithasynchronousoftheorderofMinutesRPOthatcanbeachievedwithDiskbufferedremotereplicationofthe

    orderofhours

    3.Discusstheeffectsofabunkerfailureinathreesitereplicationforthefollowingimplementation:

    Multihopsynchronous+diskbuffered

    Multihopsynchronous+asynchronous

    Multitarget

    Solution/Hint:

    Multihopsynchronous+diskbuffered

    Sameassynchronous+asynchronous

    Multihopsynchronous+asynchronous

    Ifthereisadisasteratthebunkersiteorifthereisanetworklinkfailure

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    betweenthesourceandbunkersites,thesourcesitewillcontinuetooperateasnormalbutwithoutanyremotereplication.Thissituationisverysimilartotwositereplicationwhenafailure/disasteroccursatthetargetsite.Theupdatestotheremotesitecannotoccurduetothefailureinthebunkersite.Hence,thedataattheremotesitekeepsfallingbehind;buttheadvantagehereisthatifthesourcefailsaswellduringthistime,operationscanberesumedattheremotesite.RPOattheremotesitedependsonthetimedifferencebetweenthebunkersitefailureandsourcesitefailure.

    Multitarget

    Afailureofthebunkerortheremotesiteisnotconsideredadisasterbecausenormaloperationscancontinueatthesourcesitewhileremotedisasterrecoveryprotectionisstillavailablewiththesitethathasnotfailed.Anetworklinkfailuretoeitherthebunkersite(target1)orthe

    remotesite(target2)enablesbusinessoperationstocontinueuninterruptedatthesourcesitewhileremotedisasterrecoveryprotectionisstillavailablewiththesitethatcanbereached.

    4.Discusstheeffectsofasourcefailureinathreesitereplicationforthefollowingimplementation,andtheavailablerecoveryoptions:

    Multihopsynchronous+diskbuffered

    Multihopsynchronous+asynchronous

    Multitarget

    Solution/Hint:

    Multihopsynchronous+diskbuffered

    Sameassynchronous+asynchronous

    Multihopsynchronous+asynchronous

    Ifthereisadisasteratthesource,operationsarefailedovertothebunkersitewithzeroornearzerodataloss.Butunlikethesynchronoustwositesituation,thereisstillremoteprotectionatthethirdsite.TheRPObetweenthebunkerandthirdsitecouldbeontheorderofminutes.

    Multitarget

    Ifasourcesitedisasteroccurs,BCoperationscanbestartedwiththebunker(target1)ortheremotesite(target2).Undernormalcircumstances,thedataatthebunkersiteisthemorerecentandupto

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    date.Hence,operationsareresumedwiththebunkersitedata.Insomecircumstances,thedataontheremotesiteismorecurrentthanthedataonthebunkersiteforexample,ifthenetworklinksbetweenthesourceandbunkersiteshasfailed.Inthiscase,theworkloadwouldcontinueatthesourcesitewithjusttheasynchronousreplicationtotheremotesite.Ifthesynchronouslinksaredownlongenough,thenthedataattheremotesitewouldbemorecurrentthanthedataatthebunkersite.Ifasourcesitedisasteroccursatthistime,thedataontheremotesiteshouldbeusedtorecover.Thenetworklinksbetweenthebunkerandremotesitesareactivatedinthissituationtoperformincrementalsynchronization.TheRPOisnearzeroifthebunkersitedataisused,anditisinminutesiftheremotesitedataisused.

    5.Ahostgenerates8,000I/OsatpeakutilizationwithanaverageI/Osizeof32KB.Theresponsetimeiscurrentlymeasuredatanaverageof12msduringpeakutilizations.WhensynchronousreplicationisimplementedwithaFibreChannellinktoaremotesite,whatistheresponsetimeexperiencedbythehostifthenetworklatencyis6msperI/O?

    Solution/Hint:

    Actualresponsetime=12+(6*4)+(32*1024/8000)=40.096Where12ms=currentresponsetime6msperI/O=latency32*1024/8000=datatransfertime

    Chapter15

    1.Researchthefollowingsecurityprotocolsandexplainhowtheyareused:Hint:Researchwork

    2.Astoragearraydialsasupportcenterautomaticallywheneveranerrorisdetected.Thevendor'srepresentativeatthesupportcentercanlogontotheserviceprocessorofthestoragearraythroughtheInternettoperformdiagnosticsandrepair.Discusstheimpactofthisfeatureinasecurestorageenvironmentandprovidesecuritymethodsthatcanbeimplementedtomitigateanymaliciousattacksthroughthisgateway.

    Solution/Hint:

    Modificationattacks

    Inamodificationattack,theunauthorizeduserattemptstomodifyinformationformaliciouspurposes.Amodificationattackcantargetdataatrestordataintransit.Theseattacksposeathreattodataintegrity.DenialofService

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    DenialofService(DoS)attacksdeniestheuseofresourcestolegitimateusers.Theseattacksgenerallydonotinvolveaccesstoormodificationofinformationonthecomputersystem.Instead,theyposeathreattodataavailability.TheintentionalfloodingofanetworkorwebsitetopreventlegitimateaccesstoauthorizedusersisoneexampleofaDoSattack.

    Eavesdropping

    Whensomeoneoverhearsaconversation,theunauthorizedaccessiscalledEavesdropping.Snooping

    Thisreferstoaccessinganotheruser'sdatainanunauthorizedway.Ingeneral,snoopingandeavesdroppingaresynonymous.Managementaccess

    Managementaccess,whethermonitoring,provisioning,ormanagingstorageresources,isassociatedwitheverydevicewithinthestoragenetwork.MostmanagementsoftwaresupportssomeformofCLI,systemmanagementconsoleorawebbasedinterface.SControllingadministrativeaccess

    Controllingadministrativeaccesstostorageaimstosafeguardagainstthethreatsofanattackerspoofinganadministrator'sidentityorelevatinganotheruser'sidentityandprivilegestogainadministrativeaccess.Bothofthesethreatsaffecttheintegrityofdataanddevices.Toprotectagainstthesethreats,administrativeaccessregulationandvariousauditingtechniquesareusedtoenforceaccountability.fProtectingthemanagementinfrastructure

    Protectingthemanagementnetworkinfrastructureisalsonecessary.Controlstoprotectthemanagementnetwork

    infrastructureincludeencryptingmanagementtraffic,enforcingmanagementaccesscontrols,andapplyingIPnetworksecuritybestpractices.ThesebestpracticesincludetheuseofIProutersandEthernetswitchestorestricttraffictocertaindevicesandmanagementprotocols.

    3.DevelopachecklistforauditingthesecurityofastorageenvironmentwithSAN,NAS,andiSCSIimplementations.Explainhowyouwillperformtheaudit.Assumethatyoudiscoveratleastfivesecurityloopholesduringtheauditprocess.Listthemandprovidecontrolmechanismsthatshouldbeimplementedtoeliminatethem.

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    Solution/Hint:

    SAN,NAS,iSCSI

    Servers(Production,management,backup,thirdparty,NAS)

    oWhatdataorobjectwasaccessed/attemptedtoaccess?

    oWhatactionwasperformed?

    oWhenwasexecuted?

    oWhoauthorizedandperformedtheaction?

    oNFS/CIFSaccess(sharedfiles)

    Fabric/IPnetwork

    oPhysicalandlogicalaccess

    Switches

    oPhysicalandlogicalaccessoZoning

    Storage

    oWhichvolumewasaccessed/attemptedtoaccess?

    oWhatactionwasperformed?

    oWhenwasexecuted?

    oWhoauthorizedandperformedtheaction?

    oLUNmasking

    oProvisioning

    oUpgrade/replacement

    oHandlingofphysicalmedia

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    Process

    Collectlogandcorrelate

    Analyzeaccessandchangecontrol

    oProductionandDRsiteoBackupandreplicationoThirdpartyservice

    Checkalertingmechanism

    Checksecuritycontrols

    oPhysical

    oAdministrative

    oTechnological

    Identifysecuritygap

    Documentationandrecommendation

    Fivesecurityloopholes

    1.Authenticationallowsmultiplelogin

    2.Nofirewall

    3.Noauthenticationattheswitchlevel

    4.Noencryptionforinflightdata

    5.Poorphysicalsecurityatthedatacenter

    Control

    1.Restrictioninnumberofloginattempt,twopartpassword

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    2.Implementfirewalltoblockinappropriateordangeroustraffic

    3.Authenticateusers/administratorsofFCswitchesusingRADIUS(RemoteAuthenticationDialInUserService),DHCHAP(DiffieHellmanChallengeHandshakeAuthenticationProtocol),etc.

    4.Encryptingthetrafficintransit

    5.Increasesecuritymanpowerandimplementbiometricsecurity

    Chapter16

    1.DownloadEMCControlCentersimulatorandtheaccompanyinglabguidefromhttp://education.emc.com/ismbookandexecutethestepsdetailedinthelabguide.

    Labexercise

    2.Aperformanceproblemhasbeenreportedonadatabase.Monitoringconfirmsthatat12:00a.m.,aproblemsurfaced,andaccesstothedatabaseisseverelyaffecteduntil3:00p.m.everyday.Thistimeslotiscriticalforbusinessoperationsandaninvestigationhasbeenlaunched.Areportingprocessthatstartsat12:00p.m.contendsfordatabaseresourcesandconstrainstheenvironment.Whatmonitoringandmanagementprocedures,tools,andalertswouldyouestablishtoensureaccessibility,capacity,performance,andsecurityinthisenvironment?Hints:

    Monitoring:

    Settingupmonitoringandreportingforaccessibility,capacity,performanceandsecurityonproductionandreplicationdataMonitoringandmanagementtoolssuchasECCPerformancemanagerneedtobedeploytogatherallperformancestatisticsdata(historicaldata)Performanceanalysisperformanceconstraintisbecauseoftheresource

    Management:

    Requirement:Databaseneedtobereplicateforreportingprocess

    SBasedonrequirementandinfrastructurechosenreplication

    softwareneedtobedeploySProvisionstoragecapacityforreplicationfConfiguretheenvironmentforaccessingreplicateddata(need

    configurationathost,networkandstorage)

  • 6/13/2015 Fulltextof"ISMBookExerciseSolutions.pdfUnixLabDirectory"

    https://archive.org/stream/ISMBookExerciseSolutions.pdfUnixLabDirectory/ISM%20Book%20Exercise%20Solutions.pdf%20%20Unix%20Lab%20Dire 36/36

    SConfigureadequatecapacitybasedonpolicyondataretention

    andchangeSConfiguresecurityforreplicateddata

    3.ResearchSMISandwriteatechnicalpaperondifferentvendorimplementationsofstoragemanagementsolutionsthatcomplywithSMIS.

    Researchwork